1. Field of the Invention
The present invention relates generally to a work holder assembly for bonding wire to an electronic component in a package.
2. Description of the Related Art
Electronic components are commonly formed by semiconductor chips having electrical contacts mounted onto a plastic package substrate having conductive elements forming a circuit board. The electrical contacts of the chip must be connected to the conductive elements of the package substrate to complete the circuit. It is common to solder, or wire bond, the electrical contacts with the conductive elements to complete the circuit of the electronic component. Some wire bonding processes require the electronic components to be bonded at high temperatures such as 150 degrees Celsius or higher. The components must also be held rigidly in place during the wire bonding process. One common process includes heating the package substrate in a furnace, or oven, for times ranging from 4 to 15 minutes, then transferring the package substrate to a heated wire bonding fixture for the wire bonding process. However, due to the poor thermal heat characteristics of the package and fixture, the package must often times be reheated in the wire bonding fixture to bring the package up to the specified temperature range for the wire bonding process.
Therefore, it is desirable to provide a work holder which can support the package on a continuously heated wire bonding fixture and transport the heated fixture between a heating position for directing heated gas onto the package and a wire bonding position for bonding the wire to the package.